Changing 67 Fastback rear valance

Dual exhaust isn't simple on the 67 model. Trans cross member isn't relieved both sides to clear two exhaust pipes. The one tank strap routed left to right gets in the way too. Good luck with that.
If you plan to have bumperettes/bumper guards on the 67, the font pair can be mounted on bumper bolt holes so you dont have to drill additional holes in the bumper. Try this at the back bumper and you discover the bumper guard will be right in front of the reverse lamps. A rear valance that doesn't already have the holes for reverse lamps provides opportunity to move the reverse lamps (about 3 inches left and right). You would have to add holes in the rear cross member before welding the valance on. The reverse lamp fixtures need those holes in the cross member for clearance. Any advantage to doing this?... If I get tired of looking at the bumper guards I can take them off again. Put the bumper bolts back and carry on. I have considered removing the front bumper guards and the front plate bracket ever since I put them on. The front of the car looked cleaner if not better without all that clutter. I added a lamp to that front plate and would need to undo that too. It would still have P L Y M O U T H in block letters spread all the way across the front. OEM clutter :(